Research Interests

We are interested in wave propagation in complex media, artificial structures and metamaterials, and photonic/phononic crystals.
Current research topics in our group include:
(1) Topological states in photonics and acoustics
(2) Space-time limitations in generation of surface plasmons and photons
(3) Spoof surface plasmons and surface-wave photonic crystals
(4) Multiphysics invisibility cloaking
Some illustratioins in recent papers are as follows (click for the web links):

Electrically pumped topological laser with valley edge modes, Nature, vol. 578, 246-250, Feb. 2020.

Observation of a topological nodal surface and its surface-state arcs in an artificial acoustic crystal, Nat. Commun., vol. 10, 5185, Nov. 2019.

Transformation-Invariant Metamaterials, Phys. Rev. Lett., vol. 123, 067701, Aug. 2019.

Realization of an acoustic third-order topological insulator, Phys. Rev. Lett., vol. 122, 244301, Jun. 2019.

Topological triply degenerate point with double Fermi arcs, Nat. Phys., vol. 15, 645-649, Jul. 2019.

Type-I hyperbolic metasurfaces for highly-squeezed designer polaritons with negative group velocity, Nat. Commun., vol. 10, 2002, May 2019.

Topologically Enhanced Harmonic Generation in a Nonlinear Transmission Line Metamaterial, Nat. Commun., vol. 10, 1102, Mar. 2019.

Acoustic higher-order topological insulator on a kagome lattice, Nat. Mater., vol. 18, 108-112, Feb. 2019.

Experimental observation of superscattering, Phys. Rev. Lett., vol. 122, 063901, Feb. 2019.

Realization of a three-dimensional photonic topological insulator, Nature, vol. 565, 622-626, Jan. 2019.

Superlight inverse Doppler effect, Nat. Phys., vol. 14, 1001-1005, Oct. 2018.

Controlling Cherenkov angles with resonance transition radiation, Nat. Phys., vol. 14, 816-821, Aug. 2018.

Topologically protected refraction of robust kink states in valley photonic crystals, Nat. Phys., vol. 14, 140-144, Feb. 2018.

All-angle negative refraction of highly squeezed plasmon and phonon polaritons in graphene-boron nitride heterostructures, Proc. Natl. Acad. Sci. U.S.A., vol. 114, 6717-6721, Jun. 2017.

Forward/backward switching of plasmonic wave propagation using sign-reversal coupling, Adv. Mater., vol. 29, 1700018, Jul. 2017.

Strain-induced gauge field and Landau levels in acoustic structures, Phys. Rev. Lett., vol. 118, 194301, May, 2017.

Splashing transients of 2D plasmons launched by swift electrons, Science Advances, vol. 3, no. 1, e1601192, Jan. 2017.

Acoustic type-II Weyl nodes from stacking dimerized chains, Phys. Rev. Lett., vol. 117, 224301, Nov. 2016.

Probing topological protection using a designer surface plasmon structure, Nat. Commun., vol. 7, 11619, May 2016.